Hyo Ihl Chang
Korea University
Republic of Korea
Title: Functions of natural pigments on gastric ulcer and cancer
Biography
Biography: Hyo Ihl Chang
Abstract
The Natural pigments have many applications in inflammatory, and oxidative related damage as well as in cancer chemotherapy. Recently, precise cellular roles of natural pigments, such as modulator of key cellular signaling pathway on variety diseases, are elucidated. On based on antioxidant, anthocyanins reduced naproxen-induced gastric ulcer. Anthocyanins reduced the level of lipid peroxidation and increased the level of the antioxidant enzymes. Anthocyanins increased the expression of Nuclear factor E2-related factor 2 (Nrf2) which is transactivator for cellular defense genes. Interestingly, anthocyanins induced gastrointestinal-glutathione peroxidase expression via Nrf2 that bind to regions of antioxidant response element (ARE) in GI-GPX promoter. Otherwise, Shikonin, and genipin stimulates production reactive oxygen species (ROS) in gastric cancer cells. They induced apoptotic cell death in gastric cancer cells in a caspase dependent manner. They also induced cell cycle arrest at G2/M phase via regulation of p21 by early growth response1 (Egr1). The p21 contains promoter region of Egr1 binding motif. Transient expression of Egr1 in AGS cells enhanced shikonin and genipin-induced p21 promoter activity, whereas suppression of Egr1 expression by small interfering RNA attenuated the ability of shikonin and genipin induced p21 promoter activity. Anthocyanins improve gastric ulceration through Nrf2 associated with antioxidant enzymes, such as GI-Gpx pathways. And, shikonin and genipin induced cell damage in AGS cells through the Egr1/p21 pathways.